Joakim Blikstad

This website documents my academic work up to 2025. I am currently employed in industry.

I recently was a Postdoctoral Researcher at Centrum Wiskunde & Informatica (CWI) in the Netherlands, in the field of Theoretical Computer Science. Before that, I completed my PhD at KTH Royal Institute of Technology, fortunate to be advised by Professor Danupon Nanongkai. Previously, I did my undergrad at University of Waterloo.

My reasearch was focused on combinatorial optimization topics such as matchings, maxflows, matroid intersection, and many related graph problems. I like to study these problems in many models of computations simultaneously, such as sequential, dynamic, communication, parallel, and online models.

In my free time one can often find me sailing, skiing, hiking, or playing the piano.

News

I have concluded my postdoc at CWI, where I greatly enjoyed my time. (December 2025)
I received the EATCS Distinguished Dissertation Award 2025 for my thesis.
Two papers accepted to FOCS'25: Online Edge Coloring: Sharp Thresholds and Combinatorial Maximum Flow via Weighted Push-Relabel on Shortcut Graphs.
As a jury member, I am helping to organize the European Girls' Olympiad in Informatics 2025 in Bonn, Germany, July 2025.
Global vs. s-t Vertex Connectivity Beyond Sequential: Almost-Perfect Reductions & Near-Optimal Separations accepted at STOC'25.
I joined CWI as a postdoc (February 2025).
I defended my Ph.D. November 27, 2024! [thesis]
Recipient of a Google PhD Fellowship 2023.

Older News

Deterministic Online Bipartite Edge Coloring accepted at SODA'25 and Efficient Matroid Intersection via a Batch-Update Auction Algorithm accepted at SOSA'25.
Paper accepted at FOCS'24: Maximum Flow by Augmenting Paths in n^2+o(1) Time.
As a jury member, I am helping to organize the European Girls' Olympiad in Informatics 2024 in the Netherlands, July 2024.
Invited online talk Online Edge Coloring is (Nearly) as Easy as Offline at the Toyota Technological Institute at Chicago (TTIC) [slides] [recording] (May 2024).
Two papers accepted to STOC'24: Online Edge Coloring is (Nearly) as Easy as Offline and Minimum Star Partitions of Simple Polygons in Polynomial Time.
Paper accepted to SOSA'24: Simple and Asymptotically Optimal Online Bipartite Edge Coloring.
Awarded best student paper at ESA'23: Incremental (1−ε)-approximate dynamic matching in O(poly(1/ε)) update time.
Attending the Dagstuhl Seminar on Graph Algorithms: Cuts, Flows, and Network Design, Germany, October 2023.
Visited Max Planck Institute for Informatics, May 2023 - October 2023.
As a jury member, I helped to organize the European Girls' Olympiad in Informatics in Lund, Sweden, July 2023.
Invited talk Fast Algorithms via Dynamic-Oracle Matroids at the ETH Zürich online Algorithms and Complexity Seminar [recording] (May 2023).
Visited Ola Svensson at EPFL, Switzerland, February-April 2023.
Attended the Workshop on New Directions in Geometric Algorithms, Utrecht, Netherlands, May 2023.
Paper accepted to STOC'23: Fast Algorithms via Dynamic-Oracle Matroids.
Attended the Santiago January 2023 Workshop in Combinatorial Optimization, Chile.
Ranked 13th in the ICPC world finals (Dhaka, Bangladesh, 2023), together with my teammates Nicole Hedblom and Tobias Glimmerfors.
Attended the Dagstuhl Seminar on Dynamic Graph Algorithms, Germany, November 2022.
Invited TCS+ talk Nearly Optimal Communication and Query Complexity of Bipartite Matching [recording] [slides] (September 2022).
Visited Max Planck Institute for Informatics, September 2022 - December 2022.
Speaker at the Bernoulli Center Workshop on Modern Trends in Combinatorial Optimization at EPFL, Switzerland, July 2022.
Attended conferences in year 2022: HALG'22, STOC'22, ICALP'22, FOCS'22 + summer schools at KTH and EPFL.
Awarded best student paper at ICALP'22: Sublinear-round Parallel Matroid Intersection.
Paper accepted to FOCS'22: Nearly Optimal Communication and Query Complexity of Bipartite Matching.
Visiting École Normale Supérieure, hosted by Chien-Chung Huang (July 2022), and the University of Sheffield, hosted by Sagnik Mukhopadhyay (June 2022).
Paper accepted to ICALP'22: Sublinear-round Parallel Matroid Intersection .
Long term visit at BARC, Copenhagen, September 2021 - May 2022.
Paper accepted to ICALP'21: Breaking O(nr) for Matroid Intersection .
Paper accepted to STOC'21: Breaking the Quadratic Barrier for Matroid Intersection.
Beginning my Ph.D. Studies September 2020.

Joakim Blikstad

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